GENERAL HISTOLOGY

Detailed explanation-1: -Microglia, the innate immune cells in the CNS, have two primary roles in the brain that are common to myelomonocytic innate immune cells in all mammalian organs: they fight off and phagocytize viruses, bacteria, and other foreign invaders, and they remove cellular debris to facilitate wound repair.

Detailed explanation-2: -Several types of cells of the immune system perform phagocytosis, such as neutrophils, macrophages, dendritic cells, and B lymphocytes. The act of phagocytizing pathogenic or foreign particles allows cells of the immune system to know what they are fighting against.

Detailed explanation-3: -Microglia are also the professional phagocytes of the brain and are able to engulf whole neurons within hours5, 6. Phagocytosis of dead and dying neurons and neuronal debris is beneficial in part because it reduces inflammation7, 8.